Bandwidth part switching for dual active protocol stack handover

ABSTRACT

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a base station may configure a bandwidth part (BWP) switching configuration of a user equipment in connection with a dual active protocol stack (DAPS) handover based at least in part on a BWP switching rule; and perform the DAPS handover. Numerous other aspects are provided.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Patent Application claims priority to U.S. Provisional PatentApplication No. 62/914,526, filed on Oct. 13, 2019, and to U.S.Provisional Patent Application No. 62/914,849, filed on Oct. 14, 2019,both entitled “BANDWIDTH PART SWITCHING FOR DUAL ACTIVE PROTOCOL STACKHANDOVER,” and both assigned to the assignee hereof. The disclosure ofthe prior Applications are considered part of and is incorporated byreference into this Patent Application.

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wirelesscommunication and to techniques and apparatuses for bandwidth part (BWP)switching for a dual active protocol stack (DAPS) handover.

BACKGROUND

Wireless communication systems are widely deployed to provide varioustelecommunication services such as telephony, video, data, messaging,and broadcasts. Typical wireless communication systems may employmultiple-access technologies capable of supporting communication withmultiple users by sharing available system resources (e.g., bandwidth,transmit power, and/or the like). Examples of such multiple-accesstechnologies include code division multiple access (CDMA) systems, timedivision multiple access (TDMA) systems, frequency-division multipleaccess (FDMA) systems, orthogonal frequency-division multiple access(OFDMA) systems, single-carrier frequency-division multiple access(SC-FDMA) systems, time division synchronous code division multipleaccess (TD-SCDMA) systems, and Long Term Evolution (LTE).LTE/LTE-Advanced is a set of enhancements to the Universal MobileTelecommunications System (UMTS) mobile standard promulgated by theThird Generation Partnership Project (3GPP).

A wireless communication network may include a number of base stations(BSs) that can support communication for a number of user equipment(UEs). A user equipment (UE) may communicate with a base station (BS)via the downlink and uplink. The downlink (or forward link) refers tothe communication link from the BS to the UE, and the uplink (or reverselink) refers to the communication link from the UE to the BS. As will bedescribed in more detail herein, a BS may be referred to as a Node B, agNB, an access point (AP), a radio head, a transmit receive point (TRP),a New Radio (NR) BS, a 5G Node B, and/or the like.

The above multiple access technologies have been adopted in varioustelecommunication standards to provide a common protocol that enablesdifferent user equipment to communicate on a municipal, national,regional, and even global level. New Radio (NR), which may also bereferred to as 5G, is a set of enhancements to the LTE mobile standardpromulgated by the Third Generation Partnership Project (3GPP). NR isdesigned to better support mobile broadband Internet access by improvingspectral efficiency, lowering costs, improving services, making use ofnew spectrum, and better integrating with other open standards usingorthogonal frequency division multiplexing (OFDM) with a cyclic prefix(CP) (CP-OFDM) on the downlink (DL), using CP-OFDM and/or SC-FDM (e.g.,also known as discrete Fourier transform spread OFDM (DFT-s-OFDM)) onthe uplink (UL), as well as supporting beamforming, multiple-inputmultiple-output (MIMO) antenna technology, and carrier aggregation.However, as the demand for mobile broadband access continues toincrease, there exists a need for further improvements in LTE and NRtechnologies. Preferably, these improvements should be applicable toother multiple access technologies and the telecommunication standardsthat employ these technologies.

SUMMARY

In some aspects, a method of wireless communication, performed by a basestation, may include configuring a bandwidth part (BWP) switchingconfiguration of a user equipment (UE) in connection with a dual activeprotocol stack (DAPS) handover based at least in part on a BWP switchingrule; and performing the DAPS handover.

In some aspects, a method of wireless communication, performed by a UE,may include receiving a BWP switching configuration in connection with aDAPS handover, wherein the BWP switching configuration is based at leastin part on a BWP switching rule; and performing the DAPS handover.

In some aspects, a base station for wireless communication may includememory and one or more processors operatively coupled to the memory. Thememory and the one or more processors may be configured to configure aBWP switching configuration of a UE in connection with a DAPS handoverbased at least in part on a BWP switching rule; and perform the DAPShandover.

In some aspects, a UE for wireless communication may include memory andone or more processors operatively coupled to the memory. The memory andthe one or more processors may be configured to receive a BWP switchingconfiguration in connection with a DAPS handover, wherein the BWPswitching configuration is based at least in part on a BWP switchingrule; and perform the DAPS handover.

In some aspects, a non-transitory computer-readable medium may store oneor more instructions for wireless communication. The one or moreinstructions, when executed by one or more processors of a base station,may cause the one or more processors to: configure a BWP switchingconfiguration of a UE in connection with a DAPS handover based at leastin part on a BWP switching rule; and perform the DAPS handover.

In some aspects, a non-transitory computer-readable medium may store oneor more instructions for wireless communication. The one or moreinstructions, when executed by one or more processors of a UE, may causethe one or more processors to: receive a BWP switching configuration inconnection with a DAPS handover, wherein the BWP switching configurationis based at least in part on a BWP switching rule; and perform the DAPShandover.

In some aspects, an apparatus for wireless communication may includemeans for configuring a BWP switching configuration of a UE inconnection with a DAPS handover based at least in part on a BWPswitching rule; and means for performing the DAPS handover.

In some aspects, an apparatus for wireless communication may includemeans for receiving a BWP switching configuration in connection with aDAPS handover, wherein the BWP switching configuration is based at leastin part on a BWP switching rule; and means for performing the DAPShandover.

Aspects generally include a method, apparatus, system, computer programproduct, non-transitory computer-readable medium, user equipment, basestation, wireless communication device, and/or processing system assubstantially described herein with reference to and as illustrated bythe accompanying drawings.

The foregoing has outlined rather broadly the features and technicaladvantages of examples according to the disclosure in order that thedetailed description that follows may be better understood. Additionalfeatures and advantages will be described hereinafter. The conceptionand specific examples disclosed may be readily utilized as a basis formodifying or designing other structures for carrying out the samepurposes of the present disclosure. Such equivalent constructions do notdepart from the scope of the appended claims. Characteristics of theconcepts disclosed herein, both their organization and method ofoperation, together with associated advantages will be better understoodfrom the following description when considered in connection with theaccompanying figures. Each of the figures is provided for the purposesof illustration and description, and not as a definition of the limitsof the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the above-recited features of the present disclosure can beunderstood in detail, a more particular description, briefly summarizedabove, may be had by reference to aspects, some of which are illustratedin the appended drawings. It is to be noted, however, that the appendeddrawings illustrate only certain typical aspects of this disclosure andare therefore not to be considered limiting of its scope, for thedescription may admit to other equally effective aspects. The samereference numbers in different drawings may identify the same or similarelements.

FIG. 1 is a block diagram conceptually illustrating an example of awireless communication network, in accordance with various aspects ofthe present disclosure.

FIG. 2 is a block diagram conceptually illustrating an example of a basestation in communication with a UE in a wireless communication network,in accordance with various aspects of the present disclosure.

FIG. 3 is a diagram illustrating an example of a DAPS handover, inaccordance with various aspects of the present disclosure.

FIG. 4 is a diagram illustrating an example of BWP switching inassociation with a DAPS handover, in accordance with various aspects ofthe present disclosure.

FIG. 5 is a diagram illustrating an example of a target BWP that is asubset of a source BWP, in accordance with various aspects of thepresent disclosure.

FIG. 6 is a diagram illustrating an example process performed, forexample, by a base station, in accordance with various aspects of thepresent disclosure.

FIG. 7 is a diagram illustrating an example process performed, forexample, by a UE, in accordance with various aspects of the presentdisclosure.

FIG. 8 is a block diagram of an example apparatus for wirelesscommunication, in accordance with various aspects of the presentdisclosure.

FIG. 9 is a block diagram of an example apparatus for wirelesscommunication, in accordance with various aspects of the presentdisclosure.

DETAILED DESCRIPTION

Various aspects of the disclosure are described more fully hereinafterwith reference to the accompanying drawings. This disclosure may,however, be embodied in many different forms and should not be construedas limited to any specific structure or function presented throughoutthis disclosure. Rather, these aspects are provided so that thisdisclosure will be thorough and complete, and will fully convey thescope of the disclosure to those skilled in the art. Based on theteachings herein one skilled in the art should appreciate that the scopeof the disclosure is intended to cover any aspect of the disclosuredisclosed herein, whether implemented independently of or combined withany other aspect of the disclosure. For example, an apparatus may beimplemented or a method may be practiced using any number of the aspectsset forth herein. In addition, the scope of the disclosure is intendedto cover such an apparatus or method which is practiced using otherstructure, functionality, or structure and functionality in addition toor other than the various aspects of the disclosure set forth herein. Itshould be understood that any aspect of the disclosure disclosed hereinmay be embodied by one or more elements of a claim.

Several aspects of telecommunication systems will now be presented withreference to various apparatuses and techniques. These apparatuses andtechniques will be described in the following detailed description andillustrated in the accompanying drawings by various blocks, modules,components, circuits, steps, processes, algorithms, and/or the like(collectively referred to as “elements”). These elements may beimplemented using hardware, software, or combinations thereof. Whethersuch elements are implemented as hardware or software depends upon theparticular application and design constraints imposed on the overallsystem.

It should be noted that while aspects may be described herein usingterminology commonly associated with 3G and/or 4G wireless technologies,aspects of the present disclosure can be applied in othergeneration-based communication systems, such as 5G and later, includingNR technologies.

FIG. 1 is a diagram illustrating a wireless network 100 in which aspectsof the present disclosure may be practiced. The wireless network 100 maybe an LTE network or some other wireless network, such as a 5G or NRnetwork. The wireless network 100 may include a number of BSs 110 (shownas BS 110 a, BS 110 b, BS 110 c, and BS 110 d) and other networkentities. ABS is an entity that communicates with user equipment (UEs)and may also be referred to as a base station, a NR BS, a Node B, a gNB,a 5G node B (NB), an access point, a transmit receive point (TRP),and/or the like. Each BS may provide communication coverage for aparticular geographic area. In 3GPP, the term “cell” can refer to acoverage area of a BS and/or a BS subsystem serving this coverage area,depending on the context in which the term is used.

A BS may provide communication coverage for a macro cell, a pico cell, afemto cell, and/or another type of cell. A macro cell may cover arelatively large geographic area (e.g., several kilometers in radius)and may allow unrestricted access by UEs with service subscription. Apico cell may cover a relatively small geographic area and may allowunrestricted access by UEs with service subscription. A femto cell maycover a relatively small geographic area (e.g., a home) and may allowrestricted access by UEs having association with the femto cell (e.g.,UEs in a closed subscriber group (CSG)). ABS for a macro cell may bereferred to as a macro BS. ABS for a pico cell may be referred to as apico BS. A BS for a femto cell may be referred to as a femto BS or ahome BS. In the example shown in FIG. 1 , a BS 110 a may be a macro BSfor a macro cell 102 a, a BS 110 b may be a pico BS for a pico cell 102b, and a BS 110 c may be a femto BS for a femto cell 102 c. A BS maysupport one or multiple (e.g., three) cells. The terms “eNB”, “basestation”, “NR BS”, “gNB”, “TRP”, “AP”, “node B”, “5G NB”, and “cell” maybe used interchangeably herein.

In some aspects, a cell may not necessarily be stationary, and thegeographic area of the cell may move according to the location of amobile BS. In some aspects, the BSs may be interconnected to one anotherand/or to one or more other BSs or network nodes (not shown) in thewireless network 100 through various types of backhaul interfaces suchas a direct physical connection, a virtual network, and/or the likeusing any suitable transport network.

Wireless network 100 may also include relay stations. A relay station isan entity that can receive a transmission of data from an upstreamstation (e.g., a BS or a UE) and send a transmission of the data to adownstream station (e.g., a UE or a BS). A relay station may also be aUE that can relay transmissions for other UEs. In the example shown inFIG. 1 , a relay station 110 d may communicate with macro BS 110 a and aUE 120 d in order to facilitate communication between BS 110 a and UE120 d. A relay station may also be referred to as a relay BS, a relaybase station, a relay, and/or the like.

Wireless network 100 may be a heterogeneous network that includes BSs ofdifferent types, e.g., macro BSs, pico BSs, femto BSs, relay BSs, and/orthe like. These different types of BSs may have different transmit powerlevels, different coverage areas, and different impacts on interferencein wireless network 100. For example, macro BSs may have a high transmitpower level (e.g., 5 to 40 watts) whereas pico BSs, femto BSs, and relayBSs may have lower transmit power levels (e.g., 0.1 to 2 watts).

A network controller 130 may couple to a set of BSs and may providecoordination and control for these BSs. Network controller 130 maycommunicate with the BSs via a backhaul. The BSs may also communicatewith one another, e.g., directly or indirectly via a wireless orwireline backhaul.

UEs 120 (e.g., 120 a, 120 b, 120 c) may be dispersed throughout wirelessnetwork 100, and each UE may be stationary or mobile. A UE may also bereferred to as an access terminal, a terminal, a mobile station, asubscriber unit, a station, and/or the like. A UE may be a cellularphone (e.g., a smart phone), a personal digital assistant (PDA), awireless modem, a wireless communication device, a handheld device, alaptop computer, a cordless phone, a wireless local loop (WLL) station,a tablet, a camera, a gaming device, a netbook, a smartbook, anultrabook, a medical device or equipment, biometric sensors/devices,wearable devices (smart watches, smart clothing, smart glasses, smartwrist bands, smart jewelry (e.g., smart ring, smart bracelet)), anentertainment device (e.g., a music or video device, or a satelliteradio), a vehicular component or sensor, smart meters/sensors,industrial manufacturing equipment, a global positioning system device,or any other suitable device that is configured to communicate via awireless or wired medium.

Some UEs may be considered machine-type communication (MTC) or evolvedor enhanced machine-type communication (eMTC) UEs. MTC and eMTC UEsinclude, for example, robots, drones, remote devices, sensors, meters,monitors, location tags, and/or the like, that may communicate with abase station, another device (e.g., remote device), or some otherentity. A wireless node may provide, for example, connectivity for or toa network (e.g., a wide area network such as Internet or a cellularnetwork) via a wired or wireless communication link. Some UEs may beconsidered Internet-of-Things (IoT) devices, and/or may be implementedas NB-IoT (narrowband internet of things) devices. Some UEs may beconsidered a Customer Premises Equipment (CPE). UE 120 may be includedinside a housing that houses components of UE 120, such as processorcomponents, memory components, and/or the like.

In general, any number of wireless networks may be deployed in a givengeographic area. Each wireless network may support a particular RAT andmay operate on one or more frequencies. A RAT may also be referred to asa radio technology, an air interface, and/or the like. A frequency mayalso be referred to as a carrier, a frequency channel, and/or the like.Each frequency may support a single RAT in a given geographic area inorder to avoid interference between wireless networks of different RATs.In some cases, NR or 5G RAT networks may be deployed.

In some aspects, two or more UEs 120 (e.g., shown as UE 120 a and UE 120e) may communicate directly using one or more sidelink channels (e.g.,without using a base station 110 as an intermediary to communicate withone another). For example, the UEs 120 may communicate usingpeer-to-peer (P2P) communications, device-to-device (D2D)communications, a vehicle-to-everything (V2X) protocol (e.g., which mayinclude a vehicle-to-vehicle (V2V) protocol, a vehicle-to-infrastructure(V2I) protocol, and/or the like), a mesh network, and/or the like. Inthis case, the UE 120 may perform scheduling operations, resourceselection operations, and/or other operations described elsewhere hereinas being performed by the base station 110.

As indicated above, FIG. 1 is provided as an example. Other examples maydiffer from what is described with regard to FIG. 1 .

FIG. 2 shows a block diagram of a design 200 of base station 110 and UE120, which may be one of the base stations and one of the UEs in FIG. 1. Base station 110 may be equipped with T antennas 234 a through 234 t,and UE 120 may be equipped with R antennas 252 a through 252 r, where ingeneral T≥1 and R≥1.

At base station 110, a transmit processor 220 may receive data from adata source 212 for one or more UEs, select one or more modulation andcoding schemes (MCS) for each UE based at least in part on channelquality indicators (CQIs) received from the UE, process (e.g., encodeand modulate) the data for each UE based at least in part on the MCS(s)selected for the UE, and provide data symbols for all UEs. Transmitprocessor 220 may also process system information (e.g., for semi-staticresource partitioning information (SRPI) and/or the like) and controlinformation (e.g., CQI requests, grants, upper layer signaling, and/orthe like) and provide overhead symbols and control symbols. Transmitprocessor 220 may also generate reference symbols for reference signals(e.g., the cell-specific reference signal (CRS)) and synchronizationsignals (e.g., the primary synchronization signal (PSS) and secondarysynchronization signal (SSS)). A transmit (TX) multiple-inputmultiple-output (MIMO) processor 230 may perform spatial processing(e.g., precoding) on the data symbols, the control symbols, the overheadsymbols, and/or the reference symbols, if applicable, and may provide Toutput symbol streams to T modulators (MODs) 232 a through 232 t. Eachmodulator 232 may process a respective output symbol stream (e.g., forOFDM and/or the like) to obtain an output sample stream. Each modulator232 may further process (e.g., convert to analog, amplify, filter, andupconvert) the output sample stream to obtain a downlink signal. Tdownlink signals from modulators 232 a through 232 t may be transmittedvia T antennas 234 a through 234 t, respectively. According to variousaspects described in more detail below, the synchronization signals canbe generated with location encoding to convey additional information.

At UE 120, antennas 252 a through 252 r may receive the downlink signalsfrom base station 110 and/or other base stations and may providereceived signals to demodulators (DEMODs) 254 a through 254 r,respectively. Each demodulator 254 may condition (e.g., filter, amplify,downconvert, and digitize) a received signal to obtain input samples.Each demodulator 254 may further process the input samples (e.g., forOFDM and/or the like) to obtain received symbols. A MIMO detector 256may obtain received symbols from all R demodulators 254 a through 254 r,perform MIMO detection on the received symbols if applicable, andprovide detected symbols. A receive processor 258 may process (e.g.,demodulate and decode) the detected symbols, provide decoded data for UE120 to a data sink 260, and provide decoded control information andsystem information to a controller/processor 280. A channel processormay determine reference signal received power (RSRP), received signalstrength indicator (RSSI), reference signal received quality (RSRQ),channel quality indicator (CQI), and/or the like. In some aspects, oneor more components of UE 120 may be included in a housing.

On the uplink, at UE 120, a transmit processor 264 may receive andprocess data from a data source 262 and control information (e.g., forreports comprising RSRP, RSSI, RSRQ, CQI, and/or the like) fromcontroller/processor 280. Transmit processor 264 may also generatereference symbols for one or more reference signals. The symbols fromtransmit processor 264 may be precoded by a TX MIMO processor 266 ifapplicable, further processed by modulators 254 a through 254 r (e.g.,for DFT-s-OFDM, CP-OFDM, and/or the like), and transmitted to basestation 110. At base station 110, the uplink signals from UE 120 andother UEs may be received by antennas 234, processed by demodulators232, detected by a MIMO detector 236 if applicable, and furtherprocessed by a receive processor 238 to obtain decoded data and controlinformation sent by UE 120. Receive processor 238 may provide thedecoded data to a data sink 239 and the decoded control information tocontroller/processor 240. Base station 110 may include communicationunit 244 and communicate to network controller 130 via communicationunit 244. Network controller 130 may include communication unit 294,controller/processor 290, and memory 292.

Controller/processor 240 of base station 110, controller/processor 280of UE 120, and/or any other component(s) of FIG. 2 may perform one ormore techniques associated with bandwidth part (BWP) switching for adual active protocol stack (DAPS) handover, as described in more detailelsewhere herein. For example, controller/processor 240 of base station110, controller/processor 280 of UE 120, and/or any other component(s)of FIG. 2 may perform or direct operations of, for example, process 600of FIG. 6 , process 700 of FIG. 7 , and/or other processes as describedherein. Memories 242 and 282 may store data and program codes for basestation 110 and UE 120, respectively. In some aspects, memory 242 and/ormemory 282 may comprise a non-transitory computer-readable mediumstoring one or more instructions for wireless communication. Forexample, the one or more instructions, when executed by one or moreprocessors of the base station 110 and/or the UE 120, may perform ordirect operations of, for example, process 600 of FIG. 6 , process 700of FIG. 7 , and/or other processes as described herein. A scheduler 246may schedule UEs for data transmission on the downlink and/or uplink.

In some aspects, UE 120 may include means for receiving a BWP switchingconfiguration in connection with a DAPS handover, wherein the BWPswitching configuration is based at least in part on a BWP switchingrule, means for performing the DAPS handover, and/or the like. In someaspects, such means may include one or more components of UE 120described in connection with FIG. 2 , such as controller/processor 280,transmit processor 264, TX MIMO processor 266, MOD 254, antenna 252,DEMOD 254, MIMO detector 256, receive processor 258, and/or the like.

In some aspects, base station 110 may include means for configuring aBWP switching configuration of a UE in connection with a DAPS handoverbased at least in part on a BWP switching rule; means for performing theDAPS handover; means for configuring the UE to switch at least one of asource BWP or a target BWP during the DAPS handover; means forconfiguring a source BWP of the UE as a first component carrier; meansfor configuring a target BWP of the UE as a second component carrier;means for configuring a source BWP of the UE as a first leg of amulti-TRP communication; means for configuring a target BWP of the UE asa second leg of the multi-TRP communication; and/or the like. In someaspects, such means may include one or more components of base station110 described in connection with FIG. 2 , such as antenna 234, DEMOD232, MIMO detector 236, receive processor 238, controller/processor 240,transmit processor 220, TX MIMO processor 230, MOD 232, antenna 234,and/or the like.

As indicated above, FIG. 2 is provided as an example. Other examples maydiffer from what is described with regard to FIG. 2 .

A UE in connected mode may perform a handover from a source cell to atarget cell. For example, the source cell may be provided by a sourcebase station (e.g., BS 110) and the target cell may be provided by atarget base station (e.g., BS 110). Some forms of handover may beassociated with an interruption as the UE is handed over from the sourcecell to the target cell. Certain techniques may be employed to mitigatethe interruption, such as a DAPS handover, which may also be referred toas a reduction in user data interruption (RUDI) handover or amake-before-break (MBB) handover. In a DAPS handover, the UE maycontemporaneously connect to a source cell and a target cell so that theUE can communicate with less interruption than a break-before-makehandover.

In a DAPS handover, a handover command may be conveyed to a UE using aradio resource control (RRC) message, such as an RRC reconfigurationmessage. The UE may maintain contemporaneous connections to the sourcecell and the target cell during the DAPS handover. For example, the UEmay perform downlink and uplink communication on the source cell and arandom access procedure on the target cell, or may perform downlink anduplink communication on the source cell and on the target cell. The UEmay release the connection with the source cell after receiving an RRCmessage (e.g., an RRC reconfiguration message) indicating to release theconnection with the source cell.

A UE may communicate using bandwidth parts (BWPs). A BWP may be definedby various parameters, such as a frequency resource (e.g., a starting orcenter frequency and a bandwidth), a numerology (e.g., indicating asubcarrier spacing), and/or one or more other parameters for physicalchannel configuration, such as for a physical downlink control channel,a physical downlink shared channel, a physical uplink control channel, aphysical uplink shared channel, a random access channel, and/or thelike. Different BWPs can have the same or different bandwidths, centerfrequencies, subcarrier spacing, and/or the like depending on the BWPconfiguration. Multiple BWPs can be configured for a UE, and a BWP canbe activated using downlink control information (DCI). An active BWP ofthe UE may be switched from a first configured BWP to a second BWP usingDCI. Frequency resources for uplink signals and channels of the UE maybe within an uplink BWP, and frequency resources for downlink signalsand channels may be within a downlink BWP.

BWP switching during a DAPS handover may present challenges. Forexample, some UEs may not have sufficient capabilities for switchingfrom one active BWP to another active BWP during a DAPS handover, sincethis may cause interruption of the UE's communications. As anotherexample, an impact of BWP switching may be different for aninter-frequency handover (e.g., wherein the source cell and the targetcell are non-overlapped or are associated with different centerfrequencies) than for an intra-frequency handover, due to UEcapabilities regarding retuning or communication on multiplefrequencies. Still further, an impact of BWP switching may be differentwhen a BWP of the source cell at least partially overlaps a BWP of thetarget cell than when the BWPs of the source cell and the target cellare non-overlapped.

Some techniques and apparatuses described herein provide rules for BWPswitching during a DAPS handover. For example, a BWP switching rule mayindicate that BWP switching during the DAPS handover is permitted or isnot permitted. As another example, a BWP switching rule may indicatethat BWP switching is permitted or not permitted for a particularcommunication link (e.g., uplink or downlink) during the DAPS handover.As yet another example, a BWP switching rule may be based at least inpart on whether BWPs of the source cell and the target cell areoverlapped, partially overlapped, or non-overlapped. Furthermore, sometechniques and apparatuses described herein provide configuration of BWPswitching rules for a DAPS handover, configuration of BWP switchingduring a DAPS handover, and/or the like. In this way, approaches for BWPswitching during DAPS handover (or the prevention thereof) are provided,which improve stability and reliability of DAPS handover.

FIG. 3 is a diagram illustrating an example 300 of a DAPS handover, inaccordance with various aspects of the present disclosure. A sourcegNB-DU (such as BSs 110 a-110 d depicted and described in FIG. 1 , or BS110 depicted and described in FIG. 2 ) may provide a source cell for aUE (such as UEs 120 a-120 e depicted and described in FIG. 1 , or UE 120depicted and described in FIG. 2 ). The UE may be handed over from thesource cell to a target cell provided by a target gNB-DU (such as BSs110 a-110 d and BS 110). A gNB may include a central unit (CU) and/or adistributed unit (DU). A CU is a logical node that performs gNBfunctions such as transfer of user data, mobility control, radio accessnetwork (RAN) sharing, positioning, session management and/or otherfunctions not allocated exclusively to the DU. The CU may control theoperation of DUs over a front-haul interface. A DU may perform gNBfunctions that are allocated to the DU based at least in part on afunctional split between the DU and the CU. For example, a DU mayperform one or more of packet data convergence protocol (PDCP)functions, radio link control (RLC) functions, medium access control(MAC) functions, physical (PHY) layer functions, radio frequency (RF)functions, or a combination thereof. In some aspects, one or more of theabove functions may be allocated to the CU and one or more of the abovefunctions may be allocated to the DU based at least in part on thefunctional split.

As shown by reference number 305, the UE may detect an event trigger.For example, the event trigger may relate to a measurement threshold fortriggering a handover from a source cell or source master cell group(MCG) to a target cell or target MCG. When the measurement threshold issatisfied, the UE may determine that the event trigger is detected.

As shown by reference number 310, the UE may transmit a measurementreport based at least in part on detecting the event trigger. Forexample, the UE may transmit a measurement report to the gNB-CU via thesource gNB-DU. The measurement report may identify neighbor cellmeasurements for one or more cells or cell groups.

As shown by reference number 315, the gNB-CU may determine that a DAPSbased handover is to be performed based at least in part on themeasurement report. For example, the gNB-CU may select the target gNB-DUbased at least in part on a measurement identified by the measurementreport.

As shown by reference number 320, the gNB-CU may transmit a UE contextsetup request to the target gNB-DU, and the target gNB-DU may provide aUE context setup response. The UE context setup request may indicatethat the UE is to be handed over to the target gNB-DU. The target gNB-DUmay set up a UE context for the UE based at least in part on the UEcontext setup request, and may provide a UE context setup responseindicating that the UE context has been set up.

As shown by reference number 325, the gNB-CU may provide an RRCreconfiguration message to the UE. The RRC reconfiguration message shownby reference number 325 may reconfigure a cell group configuration ofthe UE and may indicate that the UE is to perform a DAPS handover from asource MCG (such as associated with the source gNB-DU) to the target MCG(such as associated with the target gNB-DU). In some aspects, the RRCreconfiguration message shown by reference number 325 may be referred toas a handover command.

As shown by reference number 330, the UE may maintain a connection tothe source gNB and the target gNB during the DAPS based handover. Forexample, the UE may maintain respective RRC connections with the sourcegNB-DU and the target gNB-DU until an RRC reconfiguration messageindicating to release the source MCG associated with the source gNB-DUis received. User plane interruption and handover latency may bereduced.

As shown by reference number 335, the UE may continue data transmissionor reception with the source gNB-DU as the UE connects to the targetgNB-DU, shown by reference number 340. For example, the UE may continuecommunication with the source gNB-DU as synchronization and a randomaccess channel (RACH) procedure are performed for the target gNB-DU.

As shown by reference number 345, the UE may transmit an indication tothe gNB-CU, via the target gNB-DU, that the RRC connectionreconfiguration is complete. For example, the UE may transmit theindication based at least in part on successfully establishing aconnection with the target gNB-DU. As shown by reference number 350, thegNB-CU may determine, based at least in part on the RRC reconfigurationcomplete message shown by reference number 345, that the connection withthe source gNB-DU is to be released. Accordingly, as shown by referencenumber 355, the gNB-CU may provide, to the source gNB-DU, a UE contextmodification request to switch the UE's MCG from the source gNB-DU tothe target gNB-DU. The source gNB-DU may provide a UE contextmodification response to the gNB-CU based at least in part on performingthe UE context modification in accordance with the UE contextmodification request.

As shown by reference number 360, the gNB-CU may provide an RRCreconfiguration message to the UE. The RRC reconfiguration message mayindicate that the UE is to release the source gNB-DU cell group (such asthe source MCG). Accordingly, as shown by reference number 365, the UEmay release the connection to the source gNB. In some aspects, aduration of the DAPS handover may be considered to be between the RRCreconfiguration message shown by reference number 325 and the UE contextrelease shown by reference number 375 of FIG. 3 . Some techniques andapparatuses described herein provide rules for BWP switching before,during, and/or after the duration of the DAPS handover.

As shown by reference number 370, the UE may provide an RRCreconfiguration complete message to the gNB-CU via the target gNB-DU.The RRC reconfiguration complete message may indicate that the UE hasestablished the connection with the target gNB-DU. Accordingly, as shownby reference number 375, the gNB-CU may release a UE context with thesource gNB-DU based at least in part on receiving the RRCreconfiguration complete message from the UE. Thus, the UE, the sourcegNB, and the target gNB may perform a DAPS based handover. In someaspects, a DAPS based handover may be referred to herein as a DAPShandover.

As indicated above, FIG. 3 is provided as an example. Other examples maydiffer from what is described with regard to FIG. 3 .

FIG. 4 is a diagram illustrating an example 400 of BWP switching inassociation with a DAPS handover, in accordance with various aspects ofthe present disclosure. As shown, example 400 includes a UE 120, agNB-CU (e.g., the gNB-CU of FIG. 3 , BS 110), a source cell, and atarget cell. The source cell may be provided by or associated with asource gNB-DU (e.g., the source gNB-DU of FIG. 3 , BS 110), and thetarget cell may be provided by or associated with a target gNB-DU (e.g.,the target gNB-DU of FIG. 3 , BS 110). In some aspects, the source celland/or the target cell may be associated with the gNB-CU. For example,the source cell and/or the target cell may be provided by a gNB-DUassociated with the gNB-CU. In some aspects, neither the source cell northe target cell may be associated with the gNB-CU. In example 400, thesource cell is a cell to which the UE 120 is connected before performinga DAPS handover, and the target cell is a cell to which the UE isconnected after performing the DAPS handover, as described in moredetail below.

As shown in FIG. 4 , and by reference number 410, the gNB-CU may provideconfiguration information to the UE 120. In some aspects, the gNB-CU mayprovide the configuration information via the source cell. In someaspects, as shown, the configuration information may configure one ormore source BWPs and/or one or more target BWPs. A source BWP is a BWPused by the UE 120 to communicate via the source cell, and a target BWPis a BWP used by the UE 120 to communicate via the target cell. A sourceBWP can include one or more of an uplink BWP or a downlink BWP. A targetBWP can include one or more of an uplink BWP or a downlink BWP. In someaspects, the configuration information may configure a BWP for the UE120 (e.g., a dedicated BWP configured using dedicated signaling and/oran initial BWP configured via system information). In some aspects, theconfiguration information may activate a configured BWP. Theconfiguration information may include system information, RRC signaling,MAC signaling, DCI, or a combination thereof.

While example 400 shows the configuration information as being receivedprior to the DAPS handover, in some aspects, at least part of theconfiguration may be received during the DAPS handover. For example, thegNB-CU may activate a BWP (e.g., a source BWP or a target BWP) duringthe DAPS handover, thereby triggering the UE 120 to switch BWPs duringthe handover in accordance with a BWP switching rule, as described inmore detail below.

In some aspects, the configuration information (e.g., and/or the gNB-CU)may configure a BWP switching configuration. A BWP switchingconfiguration may indicate information regarding BWP switching. Forexample, the BWP switching configuration may indicate informationregarding BWP switching in association with a DAPS handover. In someaspects, the BWP switching configuration may indicate a set of sourceBWPs, a set of target BWPs, an active source BWP, an active target BWP,a time at which the UE 120 is to switch an active source BWP or anactive target BWP, a BWP switching rule (described in more detailbelow), and/or the like.

In some aspects, the configuration information may indicate a BWPswitching rule. A BWP switching rule may indicate whether a UE 120 canperform a BWP switch during a DAPS handover. For example, a BWPswitching rule may indicate whether a UE 120 is permitted to perform aBWP switch during a handover. The BWP switching rule may relate to atleast one of a source BWP or a target BWP of the UE 120. In someaspects, the UE 120 may be preconfigured with the BWP switching rule.Various examples of BWP switching rules are provided below. As usedherein, a time “during a DAPS handover” can refer to a time that isbetween the event trigger 305 and the UE context release shown byreference number 375 of FIG. 3 . In some aspects, a time “during a DAPShandover” can refer to a time that is between the RRC reconfigurationmessage shown by reference number 325 and the connection release of thesource gNB-DU shown by reference number 365 of FIG. 3 . In other words,the BWP switching rule may apply when the UE is associated with both asource connection on the source cell and a target connection on thetarget cell.

In some aspects, the BWP switching rule indicates that the UE is notpermitted to switch a source BWP during the DAPS handover. For example,the BWP switching rule may indicate that source BWP switching (includingat least one of an uplink BWP or a downlink BWP) during the DAPShandover is not allowed. As used herein, “source BWP switching” refersto changing from a first active BWP on the source cell to a secondactive BWP on the source cell. In some aspects, the BWP switching ruleindicates that the UE is not permitted to switch a target BWP during theDAPS handover. For example, the BWP switching rule may indicate thattarget BWP switching (including at least one of an uplink BWP or adownlink BWP) is not allowed. As used herein, “target BWP switching”refers to changing from a first active BWP on the target cell to asecond active BWP on the target cell.

In some aspects, the BWP switching rule indicates that the UE ispermitted to switch a source BWP during the DAPS handover. For example,the BWP switching rule may indicate that source BWP switching (includingat least one of an uplink BWP or a downlink BWP) is enabled.Additionally, or alternatively, the BWP switching rule may indicate thatthe UE is permitted to switch a target BWP during the DAPS handover. Forexample, the BWP switching rule may indicate that target BWP switching(including at least one of an uplink BWP or a downlink BWP) is enabled.

In some aspects, the BWP switching rule indicates that only one of adownlink BWP or an uplink BWP can be switched during the DAPS handover.For example, the BWP switching rule may indicate that only one of a BWPassociated with a source cell or a BWP associated with a target cell canbe switched during the DAPS handover. For example, for a cell (e.g., asource cell or a target cell), a downlink BWP may be allowed to beswitched and an uplink BWP may not be allowed to be switched, or viceversa. As another example, a source downlink BWP may be allowed to beswitched whereas a target downlink BWP may not be allowed to beswitched, or vice versa.

In some aspects, the BWP switching rule may indicate that BWP switchingis permitted for a target BWP if the target BWP is a subset of a sourceBWP. For example, for an intra-frequency DAPS handover, the UE 120 mayexpect that an active downlink bandwidth part of a target cell isconfined within an active downlink bandwidth part of a source cell. Asanother example, for an intra-frequency DAPS handover, the UE 120 mayexpect that an active uplink bandwidth part of a target cell is confinedwithin an active up link bandwidth part of a source cell. Additionally,or alternatively, the BWP switching rule may indicate that BWP switchingis permitted for a source BWP if the source BWP is a subset of a targetBWP. A first BWP is a subset of a second BWP if a bandwidth of the firstBWP is included within or is coextensive with a bandwidth of the secondBWP. By mandating that the first BWP be within a bandwidth of the secondBWP, the UE can use a BWP capability of the second BWP to processsignals and channels of the first cell and the second cell during theDAPS handover.

In some aspects, the BWP switching rule may indicate that the first BWPis to be a subset of the second BWP before the BWP switch is performed.For example, in a case of an initial first BWP and a switched first BWP,the BWP switching rule may indicate that the initial first BWP is to bea subset of the second BWP before the BWP switch is performed. In someaspects, the BWP switching rule may indicate that the first BWP is to bea subset of the second BWP after the BWP switch is performed. Forexample, in a case of an initial first BWP and a switched first BWP, theBWP switching rule may indicate that the switched first BWP is to be asubset of the second BWP after the BWP switch is performed.

FIG. 5 is a diagram illustrating an example 500 of a target BWP that isa subset of a source BWP, in accordance with various aspects of thepresent disclosure. As shown, example 500 includes a source BWP, a firsttarget BWP (e.g., Target BWP 1), and a second target BWP (e.g., TargetBWP 2). As shown, in FIG. 5 , the vertical axis represents frequency.Furthermore, with regard to the first target BWP and the second targetBWP, the horizontal axis represents time. For example, the UE 120 mayswitch from the first target BWP to the second target BWP. As shown, thefirst target BWP is within a bandwidth of the source BWP (e.g., is asubset of the source BWP) and the second target BWP is not within thebandwidth of the source BWP.

If the BWP switching rule indicates that the UE 120 is permitted toswitch a target BWP if the target BWP is a subset of the source BWPbefore the BWP switch is performed, then the UE 120 may be permitted toswitch to the first target BWP, since the first target BWP is within thesource BWP. If the BWP switching rule indicates that the UE 120 ispermitted to switch a target BWP if the target BWP is a subset of thesource BWP after the BWP switch is performed, then the UE 120 may not bepermitted to switch to the second target BWP, since the second targetBWP is not within the source BWP. In some aspects, the BWP switchingrule may indicate, for an intra-frequency DAPS handover, that the UE 120expects that an active bandwidth part of a target cell is confinedwithin an active bandwidth part of a source cell. Thus, the UE 120 maydetermine that the first target BWP can be used or switched to, whereasthe second target BWP cannot be used or switched to.

Returning to FIG. 4 , in some aspects, the BWP switching rule may bebased at least in part on whether the DAPS handover is anintra-frequency handover. For example, the BWP switching rule mayindicate that BWP switching is not permitted on a communication link foran intra-frequency handover when the UE 120 is associated with a singlecommunication chain for the communication link, thus reducinginterruption on the communication link. As another example, the BWPswitching rule may indicate that BWP switching is permitted on acommunication link for an intra-frequency handover when the UE isassociated with multiple communication chains for the communicationlink, thus improving flexibility of BWP switching.

In some aspects, the BWP switching rule may indicate that BWP switchingis permitted for a first link direction and not for a second linkdirection. For example, the BWP switching rule may indicate that BWPswitching is permitted for an uplink BWP and not for a downlink BWP. Insome aspects, the BWP switching rule may indicate that BWP switching ispermitted for a source BWP and not for a target BWP. In some aspects,the BWP switching rule may indicate that BWP switching is permitted fora target BWP and not for a source BWP.

As shown by reference number 420, in example 400, the BWP switching ruleindicates that the UE 120 is permitted to switch BWPs during the DAPShandover, and that BWP switching is permitted for a target BWP if thetarget BWP is a subset of the source BWP. For example, the rule mayindicate that BWP switching is permitted for the target BWP if thetarget BWP is a subset of the source BWP before the BWP switch, or thatBWP switching is permitted for the target BWP if the target BWP is asubset of the source BWP after the BWP switch.

As shown by reference number 430, the UE 120 and the gNB-CU may performthe DAPS handover. For example, the UE 120 and the gNB-CU may performone or more of the operations described with regard to FIG. 3 . Asfurther shown, the UE 120 may be associated with one or more source BWPsand one or more target BWPs during the DAPS handover. For example, theone or more source BWPs and the one or more target BWPs may be based atleast in part on the configuration information shown by reference number410.

In some aspects, if downlink BWPs in the source cell (e.g., a downlinksource BWP) and the target cell (e.g., a downlink target BWP) are notthe same (e.g., are not fully overlapped), then the DAPS handover mayuse a downlink carrier aggregation (CA) framework (described in moredetail below) or a multi-TRP framework. In some aspects, if the uplinkBWPs in the source cell and the target cell are not the same (e.g., arenot fully overlapped), then the DAPS handover may use an uplink CAframework or a multi-TRP framework. As used herein, in the context ofBWPs, “fully overlapped” refers to two or more BWPs with the same centerfrequency and the same bandwidth.

In some aspects, if the downlink BWPs and the uplink BWPs in the sourcecell and the target cell are not the same (e.g., the downlink BWPs arenot fully overlapped with each other and the uplink BWPs are not fullyoverlapped with each other), then the DAPS handover may use a downlinkCA framework or a multi-TRP framework, and an uplink CA framework or amulti-TRP framework.

In some aspects, the DAPS handover may be an intra-frequency handover,meaning that the source cell and the target cell may be associated witha same center frequency and/or a same bandwidth. In some aspects, for anintra-frequency handover, the configuration information may configurethe same active BWP for source and target cells. For example, theconfiguration information may configure the same active BWP for sourceand target cells based at least in part on the UE having a singletransmit chain (e.g., for an uplink BWP) or a single receive chain(e.g., for a downlink BWP). As another example, for intra-frequencyhandover, the BWP switching rule may indicate that the BWP may not beswitched when the UE 120 has a single transmit chain and/or a singlereceive chain, and may indicate that the BWP may be switched when the UEhas multiple transmit chains and/or multiple receive chains. If thesource BWP and the target BWP are partially overlapped, then the UE 120may use an inter-frequency handover framework for the DAPS handover.

In some aspects, the DAPS handover may be an inter-frequency handover,meaning that the source cell and the target cell may be associated withdifferent center frequencies and/or different bandwidths. For aninter-frequency handover, the UE 120 and the gNB-CU may use a CAframework or a multi-TRP framework for handling different BWPs in sourceand target cells. In some aspects, the BWP switching rule may indicatethat BWP switching is enabled for inter-frequency handover and not forintra-frequency handover.

As shown by reference number 440, the UE 120 may perform BWP switchingbased at least in part on the BWP switching rule. For example, the UE120 may switch a target BWP associated with the target cell based atleast in part on the target BWP being a subset of the source BWP (e.g.,before the BWP switch or after the BWP switch, as described in moredetail elsewhere herein).

As shown by reference number 450, the UE 120 may release a connection tothe source cell. As shown by reference number 370, the UE 120 maytransmit an RRC reconfiguration complete message to the gNB-CU (e.g.,via the target cell) indicating that the DAPS handover is complete, asdescribed in more detail in connection with FIG. 3 .

As indicated above, FIGS. 4 and 5 are provided as one or more examples.Other examples may differ from what is described with regard to FIGS. 4and 5 .

FIG. 6 is a diagram illustrating an example process 600 performed, forexample, by a base station, in accordance with various aspects of thepresent disclosure. Example process 600 is an example where the basestation (e.g., base station 110, a gNB-CU, a gNB-DU, and/or the like)performs operations associated with BWP switching for a DAPS handover.

As shown in FIG. 6 , in some aspects, process 600 may includeconfiguring a BWP switching configuration of a UE in connection with aDAPS handover based at least in part on a BWP switching rule (block610). For example, the base station (e.g., using antenna 234, DEMOD 232,MIMO detector 236, receive processor 238, controller/processor 240,and/or the like) may configure a BWP switching configuration of a UE inconnection with a DAPS handover based at least in part on a BWPswitching rule, as described above. In some aspects, the base stationmay switch the UE from a first BWP to a second BWP in accordance withthe BWP switching rule, or may determine that the UE cannot be switchedfrom a first BWP to the second BWP in accordance with the BWP switchingrule. In some aspects, configuring a BWP switching configuration of theUE may refer to providing DCI to the UE that causes the UE to switch anactive BWP, or refraining from switching the active BWP, in accordancewith the BWP switching rule. In other words, configuring the BWPswitching configuration may not refer to performing an RRC configurationor a similar type of configuration for the UE, and may refer to the actof switching the active BWP.

As further shown in FIG. 6 , in some aspects, process 600 may includeperforming the DAPS handover (block 620). For example, the base station(e.g., using antenna 234, DEMOD 232, MIMO detector 236, receiveprocessor 238, controller/processor 240, and/or the like) may performthe DAPS handover, as described above. The base station may provide asource cell of the DAPS handover and/or a target cell of the DAPShandover.

Process 600 may include additional aspects, such as any single aspect orany combination of aspects described below and/or in connection with oneor more other processes described elsewhere herein.

In a first aspect, the BWP switching rule indicates that the UE is notpermitted to switch a source BWP during the DAPS handover. For example,the BWP switching rule may indicate that source BWP switching (includingat least one of an uplink BWP or a downlink BWP) is not allowed.

In a second aspect, alone or in combination with the first aspect, theBWP switching rule indicates that the UE is not permitted to switch atarget BWP during the DAPS handover. For example, the BWP switching rulemay indicate that target BWP switching (including at least one of anuplink BWP or a downlink BWP) is not allowed.

In a third aspect, alone or in combination with one or more of the firstand second aspects, the BWP switching rule indicates that the UE ispermitted to switch a source BWP during the DAPS handover. For example,the BWP switching rule may indicate that source BWP switching (includingat least one of an uplink BWP or a downlink BWP) is enabled.

In a fourth aspect, alone or in combination with one or more of thefirst through third aspects, the BWP switching rule indicates that theUE is permitted to switch a target BWP during the DAPS handover. Forexample, the BWP switching rule may indicate that target BWP switching(including at least one of an uplink BWP or a downlink BWP) is enabled.

In a fifth aspect, alone or in combination with one or more of the firstthrough fourth aspects, configuring the BWP switching configurationfurther comprises configuring the UE to switch at least one of a sourceBWP or a target BWP during the DAPS handover. This may include switchingthe UE's source BWP and/or target BWP (e.g., using DCI).

In a sixth aspect, alone or in combination with one or more of the firstthrough fifth aspects, the BWP switching rule indicates that only one ofa downlink BWP or an uplink BWP can be switched during the DAPShandover. In a seventh aspect, alone or in combination with one or moreof the first through sixth aspects, the BWP switching rule indicatesthat only one of a BWP associated with a source cell or a BWP associatedwith a target cell can be switched during the DAPS handover. Forexample, for a cell (e.g., a source cell or a target cell), a downlinkBWP may be allowed to be switched but an uplink BWP may not be allowedto be switched, or vice versa. As another example, a source downlink BWPmay be allowed to be switched and a target downlink BWP may not beallowed to be switched, or vice versa.

In an eighth aspect, alone or in combination with one or more of thefirst through seventh aspects, the BWP associated with the source celland the BWP associated with the target cell are one of downlink BWPs oruplink BWPs.

In a ninth aspect, alone or in combination with one or more of the firstthrough eighth aspects, the BWP switching rule indicates that BWPswitching is permitted fora target BWP if the target BWP is a subset ofa source BWP before the BWP switching is performed. In a tenth aspect,alone or in combination with one or more of the first through ninthaspects, the BWP switching rule indicates that BWP switching ispermitted for a target BWP if the target BWP is a subset of a source BWPafter the BWP switching is performed. In an eleventh aspect, alone or incombination with one or more of the first through tenth aspects, the BWPswitching rule indicates that BWP switching is permitted for a sourceBWP if the source BWP is a subset of a target BWP before the BWPswitching is performed. In a twelfth aspect, alone or in combinationwith one or more of the first through eleventh aspects, the BWPswitching rule indicates that BWP switching is permitted for a sourceBWP if the source BWP is a subset of a target BWP after the BWPswitching is performed. A first BWP may be a subset of a second BWP if abandwidth of the first BWP is included within or coextensive with abandwidth of the second BWP. For example, the first BWP may beassociated with a first cell (e.g., a source cell or a target cell) andthe second BWP may be associated with a second cell (e.g., a target cellor a source cell). In this case, the UE can use a BWP capability of thesecond BWP to process signals and channels of the first cell and thesecond cell during the DAPS handover.

In a thirteenth aspect, alone or in combination with one or more of thefirst through twelfth aspects, the DAPS handover is an intra-frequencyhandover. Additionally, or alternatively, the UE may be associated witha single communication chain, and configuring the BWP switchingconfiguration may further include configuring a same active BWP to beused for a source cell and for a target cell. In a fourteenth aspect,alone or in combination with one or more of the first through thirteenthaspects, the single communication chain is an uplink communication chainand the same active BWP is an uplink BWP. In a fifteenth aspect, aloneor in combination with one or more of the first through fourteenthaspects, the single communication chain is a downlink communicationchain and the same active BWP is a downlink BWP. For example,configuring the same active BWP for the source cell and the target cellmay be permitted at least for the case when the UE has a single transmitchain (for an uplink BWP) and/or a single receive chain (for a downlinkBWP). This enables a UE with a single communication chain to performcontemporaneous communication on the source cell and the target cell. Ifthe source BWP and the target BWP are partially overlapped, then for theDAPS handover, UE may use an inter-frequency handover framework (e.g., acarrier aggregation or multi-TRP framework, described below).

In a sixteenth aspect, alone or in combination with one or more of thefirst through fifteenth aspects, when the DAPS handover is aninter-frequency handover, configuring the BWP switching configurationfurther comprises: configuring a source BWP of the UE as a firstcomponent carrier; and configuring a target BWP of the UE as a secondcomponent carrier. In some aspects, the UE may configure a source BWP asa first component carrier and a target BWP as a second componentcarrier. This may be referred to as a carrier aggregation (CA)framework.

In a seventeenth aspect, alone or in combination with one or more of thefirst through sixteenth aspects, when the DAPS handover is aninter-frequency handover, configuring the BWP switching configurationfurther comprises: configuring a source BWP of the UE as a first leg ofa multi-transmit/receive point (multi-TRP) communication, andconfiguring a target BWP of the UE as a second leg of the multi-TRPcommunication. This may be referred to as a multi-TRP framework.

In an eighteenth aspect, alone or in combination with one or more of thefirst through seventeenth aspects, the BWP switching rule indicates thatBWP switching is not permitted on a communication link for anintra-frequency handover when the UE is associated with a singlecommunication chain for the communication link.

In a nineteenth aspect, alone or in combination with one or more of thefirst through eighteenth aspects, the BWP switching rule indicates thatBWP switching is permitted on a communication link for anintra-frequency handover when the UE is associated with multiplecommunication chains for the communication link.

In a twentieth aspect, alone or in combination with one or more of thefirst through nineteenth aspects, the BWP switching rule indicates BWPswitching is permitted for a source BWP if the source BWP contains atarget BWP. In some aspects, the source BWP contains a target BWP if thetarget BWP is a subset of the source BWP.

In a twenty-first aspect, alone or in combination with one or more ofthe first through twentieth aspects, the BWP switching rule indicatesBWP switching is permitted for a source BWP and a target BWP if thesource BWP contains a target BWP.

In some aspects, if the downlink BWPs in the source cell and the targetcell are not the same (e.g., are not fully overlapped), then the DAPShandover may use a downlink CA framework or a multi-TRP framework.

In some aspects, if the uplink BWPs in the source cell and the targetcell are not the same (e.g., are not fully overlapped), then the DAPShandover may use an uplink CA framework or a multi-TRP framework.

In some aspects, if the downlink BWPs and the uplink BWPs in the sourcecell and the target cell are not the same (e.g., the downlink BWPs arenot fully overlapped with each other and the uplink BWPs are not fullyoverlapped with each other), then the DAPS handover may use a downlinkCA framework or a multi-TRP framework and an uplink CA framework or amulti-TRP framework.

Although FIG. 6 shows example blocks of process 600, in some aspects,process 600 may include additional blocks, fewer blocks, differentblocks, or differently arranged blocks than those depicted in FIG. 6 .Additionally, or alternatively, two or more of the blocks of process 600may be performed in parallel.

FIG. 7 is a diagram illustrating an example process 700 performed, forexample, by a UE, in accordance with various aspects of the presentdisclosure. Example process 700 is an example where the UE (e.g., UE 120and/or the like) performs operations associated with BWP switching for aDAPS handover.

As shown in FIG. 7 , in some aspects, process 700 may include receivinga BWP switching configuration in connection with a DAPS handover,wherein the BWP switching configuration is based at least in part on aBWP switching rule (block 710). For example, the UE (e.g., using antenna252, DEMOD 254, MIMO detector 256, receive processor 258,controller/processor 280, and/or the like) may receive a BWP switchingconfiguration in connection with a DAPS handover, as described above. Insome aspects, the BWP switching configuration is based at least in parton a BWP switching rule.

As further shown in FIG. 7 , in some aspects, process 700 may includeperforming the DAPS handover (block 720). For example, the UE (e.g.,using antenna 252, DEMOD 254, MIMO detector 256, receive processor 258,controller/processor 280, and/or the like) may perform the DAPShandover, as described above.

Process 700 may include additional aspects, such as any single aspect orany combination of aspects described below and/or in connection with oneor more other processes described elsewhere herein.

In a first aspect, the BWP switching rule indicates that the UE is notpermitted to switch a source BWP during the DAPS handover.

In a second aspect, alone or in combination with the first aspect, theBWP switching rule indicates that the UE is not permitted to switch atarget BWP during the DAPS handover. When the BWP switching ruleindicates that the UE is not permitted to switch a BWP, then the UE mayassume that the BWP will not be switched, may not expect the BWP to beswitched, may determine an error if the BWP is switched, and/or thelike.

In a third aspect, alone or in combination with one or more of the firstand second aspects, the BWP switching rule indicates that the UE ispermitted to switch a source BWP during the DAPS handover.

In a fourth aspect, alone or in combination with one or more of thefirst through third aspects, the BWP switching rule indicates that theUE is permitted to switch a target BWP during the DAPS handover.

In a fifth aspect, alone or in combination with one or more of the firstthrough fourth aspects, the BWP switching configuration configures theUE to switch at least one of a source BWP or a target BWP during theDAPS handover.

In a sixth aspect, alone or in combination with one or more of the firstthrough fifth aspects, the BWP switching rule indicates that only one ofa downlink BWP or an uplink BWP can be switched during the DAPShandover.

In a seventh aspect, alone or in combination with one or more of thefirst through sixth aspects, the BWP switching rule indicates that onlyone of a BWP associated with a source cell or a BWP associated with atarget cell can be switched during the DAPS handover.

In an eighth aspect, alone or in combination with one or more of thefirst through seventh aspects, the BWP associated with the source celland the BWP associated with the target cell are one of: downlink BWPs,or uplink BWPs.

In a ninth aspect, alone or in combination with one or more of the firstthrough eighth aspects, the BWP switching rule indicates BWP switchingis permitted for a target BWP if the target BWP is a subset of a sourceBWP before the BWP switching is performed.

In a tenth aspect, alone or in combination with one or more of the firstthrough ninth aspects, the BWP switching rule indicates that BWPswitching is permitted for a target BWP if the target BWP is a subset ofa source BWP after the BWP switching is performed.

In an eleventh aspect, alone or in combination with one or more of thefirst through tenth aspects, the BWP switching rule indicates BWPswitching is permitted for a source BWP if the source BWP is a subset ofa target BWP before the BWP switching is performed.

In a twelfth aspect, alone or in combination with one or more of thefirst through eleventh aspects, the BWP switching rule indicates thatBWP switching is permitted for a source BWP if the source BWP is asubset of a target BWP after the BWP switching is performed.

In a thirteenth aspect, alone or in combination with one or more of thefirst through twelfth aspects, when the DAPS handover is aninter-frequency handover and the UE is associated with a singlecommunication chain, the BWP switching configuration configures a sameactive BWP to be used for a source cell and for a target cell.

In a fourteenth aspect, alone or in combination with one or more of thefirst through thirteenth aspects, the single communication chain is anuplink communication chain and the same active BWP is an uplink BWP.

In a fifteenth aspect, alone or in combination with one or more of thefirst through fourteenth aspects, the single communication chain is adownlink communication chain and the same active BWP is a downlink BWP.

In a sixteenth aspect, alone or in combination with one or more of thefirst through fifteenth aspects, when the DAPS handover is aninter-frequency handover, the BWP switching configuration configures asource BWP of the UE as a first component carrier and a target BWP ofthe UE as a second component carrier.

In a seventeenth aspect, alone or in combination with one or more of thefirst through sixteenth aspects, when the DAPS handover is aninter-frequency handover, the BWP switching configuration configures asource BWP of the UE as a first leg of a multi-TRP communication and atarget BWP of the UE as a second leg of the multi-TRP communication.

In an eighteenth aspect, alone or in combination with one or more of thefirst through seventeenth aspects, the BWP switching rule indicates thatBWP switching is not permitted on a communication link for anintra-frequency handover when the UE is associated with a singlecommunication chain for the communication link.

In a nineteenth aspect, alone or in combination with one or more of thefirst through eighteenth aspects, the BWP switching rule indicates thatBWP switching is permitted on a communication link for anintra-frequency handover when the UE is associated with multiplecommunication chains for the communication link.

In a twentieth aspect, alone or in combination with one or more of thefirst through nineteenth aspects, when the DAPS handover is anintra-frequency handover and when the source BWP and the target BWP arenot fully overlapped, the UE configures a source BWP of the UE as afirst component carrier and a target BWP of the UE as a second componentcarrier.

In a twenty-first aspect, alone or in combination with one or more ofthe first through twentieth aspects, the BWP switching rule indicatesBWP switching is permitted for a source BWP if the source BWP contains atarget BWP. In some aspects, the source BWP contains a target BWP if thetarget BWP is a subset of the source BWP.

In a twenty-second aspect, alone or in combination with one or more ofthe first through twenty-first aspects, the BWP switching rule indicatesBWP switching is permitted for a source BWP and a target BWP if thesource BWP contains a target BWP.

Although FIG. 7 shows example blocks of process 700, in some aspects,process 700 may include additional blocks, fewer blocks, differentblocks, or differently arranged blocks than those depicted in FIG. 7 .Additionally, or alternatively, two or more of the blocks of process 700may be performed in parallel.

FIG. 8 is a block diagram of an example apparatus 800 for wirelesscommunication. The apparatus 800 may be a base station, or a basestation may include the apparatus 800. In some aspects, the apparatus800 includes a reception component 802 and a transmission component 804,which may be in communication with one another (for example, via one ormore buses and/or one or more other components). As shown, the apparatus800 may communicate with another apparatus 806 (such as a UE, a basestation, or another wireless communication device) using the receptioncomponent 802 and the transmission component 804. As further shown, theapparatus 800 may include one or more of a configuration component 808or a handover component 810, among other examples.

In some aspects, the apparatus 800 may be configured to perform one ormore operations described herein in connection with FIGS. 3-5 .Additionally or alternatively, the apparatus 800 may be configured toperform one or more processes described herein, such as process 600 ofFIG. 6 . In some aspects, the apparatus 800 and/or one or morecomponents shown in FIG. 8 may include one or more components of thebase station described above in connection with FIG. 2 . Additionally,or alternatively, one or more components shown in FIG. 8 may beimplemented within one or more components described above in connectionwith FIG. 2 . Additionally or alternatively, one or more components ofthe set of components may be implemented at least in part as softwarestored in a memory. For example, a component (or a portion of acomponent) may be implemented as instructions or code stored in anon-transitory computer-readable medium and executable by a controlleror a processor to perform the functions or operations of the component.

The reception component 802 may receive communications, such asreference signals, control information, data communications, or acombination thereof, from the apparatus 806. The reception component 802may provide received communications to one or more other components ofthe apparatus 800. In some aspects, the reception component 802 mayperform signal processing on the received communications (such asfiltering, amplification, demodulation, analog-to-digital conversion,demultiplexing, deinterleaving, de-mapping, equalization, interferencecancellation, or decoding, among other examples), and may provide theprocessed signals to the one or more other components of the apparatus806. In some aspects, the reception component 802 may include one ormore antennas, a demodulator, a MIMO detector, a receive processor, acontroller/processor, a memory, or a combination thereof, of the basestation described above in connection with FIG. 2 .

The transmission component 804 may transmit communications, such asreference signals, control information, data communications, or acombination thereof, to the apparatus 806. In some aspects, one or moreother components of the apparatus 806 may generate communications andmay provide the generated communications to the transmission component804 for transmission to the apparatus 806. In some aspects, thetransmission component 804 may perform signal processing on thegenerated communications (such as filtering, amplification, modulation,digital-to-analog conversion, multiplexing, interleaving, mapping, orencoding, among other examples), and may transmit the processed signalsto the apparatus 806. In some aspects, the transmission component 804may include one or more antennas, a modulator, a transmit MIMOprocessor, a transmit processor, a controller/processor, a memory, or acombination thereof, of the base station described above in connectionwith FIG. 2 . In some aspects, the transmission component 804 may becollocated with the reception component 802 in a transceiver.

The configuration component 808 may configure a BWP switchingconfiguration of a UE in connection with a DAPS handover based at leastin part on a BWP switching rule. In some aspects, the configurationcomponent 808 may include one or more antennas, a demodulator, a MIMOdetector, a receive processor, a modulator, a transmit MIMO processor, atransmit processor, a controller/processor, a memory, or a combinationthereof, of the base station described above in connection with FIG. 2 .The handover component 810 may perform the DAPS handover. In someaspects, the handover component 810 may include one or more antennas, ademodulator, a MIMO detector, a receive processor, a modulator, atransmit MIMO processor, a transmit processor, a controller/processor, amemory, or a combination thereof, of the base station described above inconnection with FIG. 2 .

In some aspects, the configuration component 808 may configure a sameactive BWP to be used for a source cell and for a target cell. In someaspects, the configuration component 808 may configure a source BWP ofthe UE as a first component carrier. In some aspects, the configurationcomponent 808 may configure a target BWP of the UE as a second componentcarrier. In some aspects, the configuration component 808 may configurea source BWP of the UE as a first leg of a multi-TRP communication. Insome aspects, the configuration component 808 may configure a target BWPof the UE as a second leg of the multi-TRP communication.

The number and arrangement of components shown in FIG. 8 are provided asan example. In practice, there may be additional components, fewercomponents, different components, or differently arranged componentsthan those shown in FIG. 8 . Furthermore, two or more components shownin FIG. 8 may be implemented within a single component, or a singlecomponent shown in FIG. 8 may be implemented as multiple, distributedcomponents. Additionally or alternatively, a set of (one or more)components shown in FIG. 8 may perform one or more functions describedas being performed by another set of components shown in FIG. 8 .

FIG. 9 is a block diagram of an example apparatus 900 for wirelesscommunication, in accordance with various aspects of the presentdisclosure. The apparatus 900 may be a UE, or a UE may include theapparatus 900. In some aspects, the apparatus 900 includes a receptioncomponent 902 and a transmission component 904, which may be incommunication with one another (for example, via one or more busesand/or one or more other components). As shown, the apparatus 900 maycommunicate with another apparatus 906 (such as a UE, a base station, oranother wireless communication device) using the reception component 902and the transmission component 904. As further shown, the apparatus 900may include a handover component 908, among other examples.

In some aspects, the apparatus 900 may be configured to perform one ormore operations described herein in connection with FIGS. 3-5 .Additionally or alternatively, the apparatus 900 may be configured toperform one or more processes described herein, such as process 700 ofFIG. 7 . In some aspects, the apparatus 900 and/or one or morecomponents shown in FIG. 9 may include one or more components of the UEdescribed above in connection with FIG. 2 . Additionally, oralternatively, one or more components shown in FIG. 9 may be implementedwithin one or more components described above in connection with FIG. 2. Additionally or alternatively, one or more components of the set ofcomponents may be implemented at least in part as software stored in amemory. For example, a component (or a portion of a component) may beimplemented as instructions or code stored in a non-transitorycomputer-readable medium and executable by a controller or a processorto perform the functions or operations of the component.

The reception component 902 may receive communications, such asreference signals, control information, data communications, or acombination thereof, from the apparatus 906. The reception component 902may provide received communications to one or more other components ofthe apparatus 900. In some aspects, the reception component 902 mayperform signal processing on the received communications (such asfiltering, amplification, demodulation, analog-to-digital conversion,demultiplexing, deinterleaving, de-mapping, equalization, interferencecancellation, or decoding, among other examples), and may provide theprocessed signals to the one or more other components of the apparatus906. In some aspects, the reception component 902 may include one ormore antennas, a demodulator, a MIMO detector, a receive processor, acontroller/processor, a memory, or a combination thereof, of the UEdescribed above in connection with FIG. 2 .

The transmission component 904 may transmit communications, such asreference signals, control information, data communications, or acombination thereof, to the apparatus 906. In some aspects, one or moreother components of the apparatus 906 may generate communications andmay provide the generated communications to the transmission component904 for transmission to the apparatus 906. In some aspects, thetransmission component 904 may perform signal processing on thegenerated communications (such as filtering, amplification, modulation,digital-to-analog conversion, multiplexing, interleaving, mapping, orencoding, among other examples), and may transmit the processed signalsto the apparatus 906. In some aspects, the transmission component 904may include one or more antennas, a modulator, a transmit MIMOprocessor, a transmit processor, a controller/processor, a memory, or acombination thereof, of the UE described above in connection with FIG. 2. In some aspects, the transmission component 904 may be collocated withthe reception component 902 in a transceiver.

The reception component 902 may receive a BWP switching configuration inconnection with a DAPS handover, wherein the BWP switching configurationis based at least in part on a BWP switching rule. The handovercomponent 908 may perform the DAPS handover. In some aspects, thehandover component 908 may include one or more antennas, a demodulator,a MIMO detector, a receive processor, a modulator, a transmit MIMOprocessor, a transmit processor, a controller/processor, a memory, or acombination thereof, of the UE described above in connection with FIG. 2.

The number and arrangement of components shown in FIG. 9 are provided asan example. In practice, there may be additional components, fewercomponents, different components, or differently arranged componentsthan those shown in FIG. 9 . Furthermore, two or more components shownin FIG. 9 may be implemented within a single component, or a singlecomponent shown in FIG. 9 may be implemented as multiple, distributedcomponents. Additionally or alternatively, a set of (one or more)components shown in FIG. 9 may perform one or more functions describedas being performed by another set of components shown in FIG. 9 .

The foregoing disclosure provides illustration and description, but isnot intended to be exhaustive or to limit the aspects to the preciseform disclosed. Modifications and variations may be made in light of theabove disclosure or may be acquired from practice of the aspects.

As used herein, the term “component” is intended to be broadly construedas hardware, firmware, and/or a combination of hardware and software. Asused herein, a processor is implemented in hardware, firmware, and/or acombination of hardware and software.

As used herein, satisfying a threshold may, depending on the context,refer to a value being greater than the threshold, greater than or equalto the threshold, less than the threshold, less than or equal to thethreshold, equal to the threshold, not equal to the threshold, and/orthe like.

It will be apparent that systems and/or methods described herein may beimplemented in different forms of hardware, firmware, and/or acombination of hardware and software. The actual specialized controlhardware or software code used to implement these systems and/or methodsis not limiting of the aspects. Thus, the operation and behavior of thesystems and/or methods were described herein without reference tospecific software code—it being understood that software and hardwarecan be designed to implement the systems and/or methods based, at leastin part, on the description herein.

Even though particular combinations of features are recited in theclaims and/or disclosed in the specification, these combinations are notintended to limit the disclosure of various aspects. In fact, many ofthese features may be combined in ways not specifically recited in theclaims and/or disclosed in the specification. Although each dependentclaim listed below may directly depend on only one claim, the disclosureof various aspects includes each dependent claim in combination withevery other claim in the claim set. A phrase referring to “at least oneof” a list of items refers to any combination of those items, includingsingle members. As an example, “at least one of: a, b, or c” is intendedto cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combinationwith multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c,a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or any other ordering ofa, b, and c).

No element, act, or instruction used herein should be construed ascritical or essential unless explicitly described as such. Also, as usedherein, the articles “a” and “an” are intended to include one or moreitems, and may be used interchangeably with “one or more.” Furthermore,as used herein, the terms “set” and “group” are intended to include oneor more items (e.g., related items, unrelated items, a combination ofrelated and unrelated items, and/or the like), and may be usedinterchangeably with “one or more.” Where only one item is intended, thephrase “only one” or similar language is used. Also, as used herein, theterms “has,” “have,” “having,” and/or the like are intended to beopen-ended terms. Further, the phrase “based on” is intended to mean“based, at least in part, on” unless explicitly stated otherwise.

What is claimed is:
 1. A method of wireless communication performed by anetwork node, comprising: configuring a bandwidth part (BWP) switchingconfiguration of a user equipment (UE) in connection with a dual activeprotocol stack (DAPS) handover based at least in part on a BWP switchingrule associated with first BWP, associated with a source cell andcomprising a first downlink BWP and a first uplink BWP, and a secondBWP, associated with a target cell and comprising a second downlink BWPand a second uplink BWP, wherein the BWP switching rule indicates atleast one of: the second downlink BWP being a subset of the firstdownlink BWP such that a bandwidth of the second downlink BWP is withina bandwidth of the first downlink BWP, or the second uplink BWP being asubset of the first uplink BWP such that a bandwidth of the seconduplink BWP is within a bandwidth of the first uplink BWP; and performingthe DAPS handover.
 2. The method of claim 1, wherein the BWP switchingrule indicates BWP switching is permitted for the first BWP if: thefirst downlink BWP, in the first BWP, contains the second downlink BWPin the second BWP, and the first uplink BWP, in the first BWP, containsthe second uplink BWP in the second BWP.
 3. The method of claim 1,wherein the DAPS handover is an intra-frequency handover.
 4. The methodof claim 1, wherein configuring the BWP switching configuration furthercomprises: configuring the UE to switch at least one of the first BWP orthe second BWP during the DAPS handover.
 5. The method of claim 1,wherein, when the DAPS handover is an inter-frequency handover,configuring the BWP switching configuration further comprises:configuring the first BWP as a first component carrier; and configuringthe second BWP as a second component carrier.
 6. The method of claim 1,wherein, when the DAPS handover is an inter-frequency handover,configuring the BWP switching configuration further comprises:configuring the first BWP as a first leg of a multi-transmit/receivepoint (multi-TRP) communication; and configuring the second BWP as asecond leg of the multi-TRP communication.
 7. The method of claim 1,wherein the BWP switching rule indicates that BWP switching is notpermitted on a communication link for an intra-frequency handover whenthe UE is associated with a single communication chain for thecommunication link.
 8. The method of claim 1, wherein the BWP switchingrule indicates that BWP switching is permitted on a communication linkfor an intra-frequency handover when the UE is associated with multiplecommunication chains for the communication link.
 9. The method of claim1, wherein the BWP switching rule indicates that the second downlink BWPis the subset of the first downlink BWP such that the bandwidth of thesecond downlink BWP is within the bandwidth of the first downlink BWP,and wherein the target first downlink BWP and the source second downlinkBWP are each active.
 10. The method of claim 1, wherein the BWPswitching rule indicates that the second uplink BWP is the subset of thefirst uplink BWP such that the bandwidth of the second uplink BWP iswithin the bandwidth of the first uplink BWP, and wherein the targetfirst uplink BWP and the source second uplink BWP are each active.
 11. Amethod of wireless communication performed by a user equipment (UE),comprising: receiving a bandwidth part (BWP) switching configuration inconnection with a dual active protocol stack (DAPS) handover, whereinthe BWP switching configuration is based at least in part on a BWPswitching rule associated with first BWP, associated with a source celland comprising first downlink BWP and first uplink BWP, and a secondBWP, associated with a target cell and comprising a second downlink BWPand a second uplink BWP, wherein the BWP switching rule indicates atleast one of: the second downlink BWP being a subset of the firstdownlink BWP such that a bandwidth of the second downlink BWP is withina bandwidth of the first downlink BWP, or the second uplink BWP being asubset of the first uplink BWP such that a bandwidth of the seconduplink BWP is within a bandwidth of the first uplink BWP; and performingthe DAPS handover.
 12. The method of claim 11, wherein the BWP switchingrule indicates BWP switching is permitted for the first BWP if: thefirst downlink BWP, in the first BWP<contains the second downlink BWP inthe second BWP, and the first uplink BWP, in the first BWP, contains thesecond uplink BWP in the second BWP.
 13. The method of claim 11,wherein, when the DAPS handover is an intra-frequency handover.
 14. Themethod of claim 11, wherein the BWP switching rule indicates that thesecond downlink BWP is the subset of the first downlink BWP such thatthe bandwidth of the second downlink BWP is within the bandwidth of thefirst downlink BWP, and wherein the target first downlink BWP and thesource second downlink BWP are each active.
 15. The method of claim 11,wherein the BWP switching rule indicates that the second uplink BWP isthe subset of the first uplink BWP such that the bandwidth of the seconduplink BWP is within the bandwidth of the first uplink BWP, and whereinthe target first uplink BWP and the source second uplink BWP are eachactive.
 16. The method of claim 11, wherein receiving the BWP switchingconfiguration comprises: receiving the BWP switching configurationduring the DAPS handover.
 17. A network node for wireless communication,comprising: a memory; and one or more processors coupled to the memory,the one or more processors configured to: configure a bandwidth part(BWP) switching configuration of a user equipment (UE) in connectionwith a dual active protocol stack (DAPS) handover based at least in parton a BWP switching rule associated with first BWP, associated with asource cell and comprising first downlink BWP and first uplink BWP, anda second BWP, associated with a target cell and comprising a seconddownlink BWP and a second uplink BWP, wherein the BWP switching ruleindicates at least one of: the second downlink BWP being a subset of thefirst downlink BWP such that a bandwidth of the second downlink BWP iswithin a bandwidth of the first downlink BWP, or the second uplink BWPbeing a subset of the first uplink BWP such that a bandwidth of thesecond uplink BWP is within a bandwidth of the first uplink BWP; andperform the DAPS handover.
 18. The network node of claim 17, wherein theBWP switching rule indicates BWP switching is permitted for the firstBWP if: the first downlink BWP, in the first BWP, contains the seconddownlink BWP in the second BWP, and the first uplink BWP, in the firstBWP, contains the second uplink BWP in the second BWP.
 19. The networknode of claim 17, wherein the DAPS handover is an intra-frequencyhandover.
 20. The network node of claim 17, wherein the BWP switchingrule indicates that the second downlink BWP is the subset of the firstdownlink BWP such that the bandwidth of the second downlink BWP iswithin the bandwidth of the first downlink BWP, and wherein the targetfirst downlink BWP and the source second downlink BWP are each active.21. The network node of claim 17, wherein the BWP switching ruleindicates that the second uplink BWP is the subset of the first uplinkBWP such that the bandwidth of the second uplink BWP is within thebandwidth of the first uplink BWP, and wherein the target first uplinkBWP and the source second uplink BWP are each active.
 22. The networknode of claim 17, wherein the one or more processors are furtherconfigured to: provide the BWP switching configuration during the DAPShandover.
 23. A user equipment (UE) for wireless communication,comprising: a memory; and one or more processors coupled to the memory,the one or more processors configured to: receive a bandwidth part (BWP)switching configuration in connection with a dual active protocol stack(DAPS) handover, wherein the BWP switching configuration is based atleast in part on a BWP switching rule associated with first BWP,associated with a source cell and comprising first downlink BWP and afirst uplink BWP, and a second BWP, associated with a target cell andcomprising a second downlink BWP and a second uplink BWP, wherein theBWP switching rule indicates at least one of: the second downlink BWPbeing a subset of the first downlink BWP such that a bandwidth of thesecond downlink BWP is within a bandwidth of the first downlink BWP, orthe second uplink BWP being a subset of the first uplink BWP such that abandwidth of the second uplink BWP is within a bandwidth of the firstuplink BWP; and perform the DAPS handover.
 24. The UE of claim 23,wherein the BWP switching rule indicates BWP switching is permitted forthe first BWP if: the first downlink BWP, in the first BWP, contains thesecond downlink BWP in the second BWP, and the first uplink BWP, in thefirst BWP, contains the second uplink BWP in the second BWP.
 25. The UEof claim 23, wherein, when the DAPS handover is an intra-frequencyhandover.
 26. The UE of claim 23, wherein the BWP switching ruleindicates that the second downlink BWP is the subset of the firstdownlink BWP such that the bandwidth of the second downlink BWP iswithin the bandwidth of the first downlink BWP, and wherein the targetfirst downlink BWP and the source second downlink BWP are each active.27. The UE of claim 23, wherein the BWP switching rule indicates thatthe second uplink BWP is the subset of the first uplink BWP such thatthe bandwidth of the second uplink BWP is within the bandwidth of thefirst uplink BWP, and wherein the target first uplink BWP and the sourcesecond uplink BWP are each active.
 28. The UE of claim 23, wherein, toreceive the BWP switching configuration, the one or more processors arefurther configured to: receive the BWP switching configuration duringthe DAPS handover.
 29. The UE of claim 23, wherein the BWP switchingrule indicates that BWP switching is not permitted on a communicationlink for an intra-frequency handover when the UE is associated with asingle communication chain for the communication link.
 30. The UE ofclaim 23, wherein the BWP switching rule indicates that BWP switching ispermitted on a communication link for an intra-frequency handover whenthe UE is associated with multiple communication chains for thecommunication link.
 31. An apparatus for wireless communication,comprising: means for configuring a bandwidth part (BWP) switchingconfiguration of a user equipment (UE) in connection with a dual activeprotocol stack (DAPS) handover based at least in part on a BWP switchingrule associated with first BWP, associated with a source cell andcomprising first downlink BWP and first uplink BWP, and a second BWP,associated with a target cell and comprising a second downlink BWP and asecond uplink BWP, wherein the BWP switching rule indicates at least oneof: the second downlink BWP being a subset of the first downlink BWPsuch that a bandwidth of the second downlink BWP is within a bandwidthof the first downlink BWP, or the second uplink BWP being a subset ofthe first uplink BWP such that a bandwidth of the second uplink BWP iswithin a bandwidth of the first uplink BWP; and means for performing theDAPS handover.
 32. The apparatus of claim 31, wherein the BWP switchingrule indicates BWP switching is permitted for the first BWP if: thefirst downlink BWP, in the first BWP, contains the second downlink BWPin the second BWP, and the first uplink BWP, in the first BWP, containsthe second uplink BWP in the second BWP.
 33. The apparatus of claim 31,wherein the DAPS handover is an intra-frequency handover.
 34. Theapparatus of claim 31, wherein the means for configuring the BWPswitching configuration further comprises: means for configuring the UEto switch at least one of the first BWP or the second BWP during theDAPS handover.
 35. The apparatus of claim 31, wherein, when the DAPShandover is an inter-frequency handover, the means for configuring theBWP switching configuration further comprises: means for configuring thefirst BWP as a first component carrier; and means for configuring thesecond BWP as a second component carrier.
 36. The apparatus of claim 31,wherein, when the DAPS handover is an inter-frequency handover, themeans for configuring the BWP switching configuration further comprises:means for configuring the first BWP as a first leg of amulti-transmit/receive point (multi-TRP) communication; and means forconfiguring the second BWP as a second leg of the multi-TRPcommunication.
 37. The apparatus of claim 31, wherein the BWP switchingrule indicates that BWP switching is not permitted on a communicationlink for an intra-frequency handover when the UE is associated with asingle communication chain for the communication link.
 38. The apparatusof claim 31, wherein the BWP switching rule indicates that BWP switchingis permitted on a communication link for an intra-frequency handoverwhen the UE is associated with multiple communication chains for thecommunication link.
 39. The apparatus of claim 31, wherein the BWPswitching rule indicates that the second downlink BWP is the subset ofthe first downlink BWP such that the bandwidth of the second downlinkBWP is within the bandwidth of the first downlink BWP, and wherein thetarget first downlink BWP and the source second downlink BWP are eachactive.
 40. The apparatus of claim 31, wherein the BWP switching ruleindicates that the second uplink BWP is the subset of the first uplinkBWP such that the bandwidth of the second uplink BWP is within thebandwidth of the first uplink BWP, and wherein the target first uplinkBWP and the source second uplink BWP are each active.
 41. An apparatusfor wireless communication, comprising: means for receiving a bandwidthpart (BWP) switching configuration in connection with a dual activeprotocol stack (DAPS) handover, wherein the BWP switching configurationis based at least in part on a BWP switching rule associated with firstBWP, associated with a source cell and comprising first downlink BWP andfirst uplink BWP, and a second BWP, associated with a target cell andcomprising a second downlink BWP and a second uplink BWP, wherein theBWP switching rule indicates at least one of: the second downlink BWPbeing a subset of the first downlink BWP such that a bandwidth of thesecond downlink BWP is within a bandwidth of the first downlink BWP, orthe second uplink BWP being a subset of the first uplink BWP such that abandwidth of the second uplink BWP is within a bandwidth of the firstuplink BWP; and performing the DAPS handover.
 42. The apparatus of claim41, wherein the BWP switching rule indicates BWP switching is permittedfor the first BWP if: the first downlink BWP, in the first BWP, containsthe second downlink BWP in the second BWP, and the first uplink BWP, inthe first BWP, contains the second uplink BWP in the second BWP.
 43. Theapparatus of claim 41, wherein, when the DAPS handover is anintra-frequency handover.
 44. The apparatus of claim 41, wherein the BWPswitching rule indicates that the second downlink BWP is the subset ofthe first downlink BWP such that the bandwidth of the second downlinkBWP is within the bandwidth of the first downlink BWP, and wherein thetarget first downlink BWP and the source second downlink BWP are eachactive.
 45. The apparatus of claim 41, wherein the BWP switching ruleindicates that the second uplink BWP is the subset of the first uplinkBWP such that the bandwidth of the second uplink BWP is within thebandwidth of the first uplink BWP, and wherein the target first uplinkBWP and the source second uplink BWP are each active.
 46. The apparatusof claim 41, wherein the means for receiving the BWP switchingconfiguration comprises: means for receiving the BWP switchingconfiguration during the DAPS handover.